WO1988007109A1 - Procede servant a empecher le gel dans des conduites et systeme de conduite permettant de realiser ledit procede - Google Patents

Procede servant a empecher le gel dans des conduites et systeme de conduite permettant de realiser ledit procede Download PDF

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Publication number
WO1988007109A1
WO1988007109A1 PCT/SE1988/000133 SE8800133W WO8807109A1 WO 1988007109 A1 WO1988007109 A1 WO 1988007109A1 SE 8800133 W SE8800133 W SE 8800133W WO 8807109 A1 WO8807109 A1 WO 8807109A1
Authority
WO
WIPO (PCT)
Prior art keywords
water
pressure
pipe
safety valve
pipe portion
Prior art date
Application number
PCT/SE1988/000133
Other languages
English (en)
Inventor
Anders Westerberg
Original Assignee
Anders Westerberg
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Anders Westerberg filed Critical Anders Westerberg
Priority to AT88902971T priority Critical patent/ATE66032T1/de
Priority to DE8888902971T priority patent/DE3864142D1/de
Publication of WO1988007109A1 publication Critical patent/WO1988007109A1/fr
Priority to DK637388A priority patent/DK164178C/da
Priority to NO885115A priority patent/NO163461C/no
Priority to FI894367A priority patent/FI87001C/fi

Links

Classifications

    • A—HUMAN NECESSITIES
    • A62—LIFE-SAVING; FIRE-FIGHTING
    • A62C—FIRE-FIGHTING
    • A62C3/00—Fire prevention, containment or extinguishing specially adapted for particular objects or places
    • A62C3/002—Fire prevention, containment or extinguishing specially adapted for particular objects or places for warehouses, storage areas or other installations for storing goods
    • A62C3/004—Fire prevention, containment or extinguishing specially adapted for particular objects or places for warehouses, storage areas or other installations for storing goods for freezing warehouses and storages
    • E—FIXED CONSTRUCTIONS
    • E03—WATER SUPPLY; SEWERAGE
    • E03B—INSTALLATIONS OR METHODS FOR OBTAINING, COLLECTING, OR DISTRIBUTING WATER
    • E03B7/00—Water main or service pipe systems
    • E03B7/09—Component parts or accessories
    • E03B7/10—Devices preventing bursting of pipes by freezing
    • E03B7/12—Devices preventing bursting of pipes by freezing by preventing freezing
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
    • F16K15/00—Check valves
    • F16K15/02—Check valves with guided rigid valve members
    • F16K15/06—Check valves with guided rigid valve members with guided stems
    • F16K15/063—Check valves with guided rigid valve members with guided stems the valve being loaded by a spring
    • F16K15/066—Check valves with guided rigid valve members with guided stems the valve being loaded by a spring with a plurality of valve members
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
    • F16K17/00—Safety valves; Equalising valves, e.g. pressure relief valves
    • F16K17/02—Safety valves; Equalising valves, e.g. pressure relief valves opening on surplus pressure on one side; closing on insufficient pressure on one side
    • F16K17/04—Safety valves; Equalising valves, e.g. pressure relief valves opening on surplus pressure on one side; closing on insufficient pressure on one side spring-loaded
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/1189—Freeze condition responsive safety systems
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/7722—Line condition change responsive valves
    • Y10T137/7837—Direct response valves [i.e., check valve type]
    • Y10T137/7838—Plural
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/7722—Line condition change responsive valves
    • Y10T137/7837—Direct response valves [i.e., check valve type]
    • Y10T137/785—With retarder or dashpot

Definitions

  • the present invention relates to a method of preventing freezing in pipes for carrying water.
  • the invention also relates to a piping system for carrying out the method in accordance with the preamble to the accompanying claim 2.
  • Freezing in water carrying piping is a very great problem in all countries with a cold winter climate. Apart from the immediate problem of being without water, pipe damage and subsequent water damage on thawing cost enormous amounts every year. Since the previous century, much thought and effort have been put into finding a reliable and practicably executable solution to this problem.
  • a waste valve is known from SE-C 210 736 with an upper chamber filled with water, which is assumed to freeze before the water in the piping freezes.
  • the expansion on the formation of ice in the upper chamber actuates a waste valve causing it to open and allow the water in the piping to flow out.
  • the uncertainty factors in this structure are several, e.g. the assumption that freezing will first take place in the upper chamber and that the water flowing out from the opened valve will melt the ice in the upper chamber and allow the valve to return to its closed position. This valve has thus not been used to any great extent.
  • the US-A-641 308 teaches a tap with a temperature-sensi ⁇ tive element in the tap which opens the tap at low tempe ⁇ ratures. This solution has the great disadvantage that the temperature is only measured at the tap.
  • the same prin ⁇ ciple with a temperature-sensitive element is used in the US-A-4 117 856.
  • the SE patent specification 103 613 uti ⁇ lizes an adjustable, continuously open shut duct and a rubber flap which opens at a subpressure caused by ice formation in the pipe. The valve thus does not prevent ice formation in the pipe, and furthermore it requires a con ⁇ tinuously running jet of water.
  • the present invention has the object of providing a method of preventing freezing in pipes and a piping system for carrying out the method which avoids the above-mentioned disadvantages. This is achieved by a method of the type described in the introduction, which has the characteri ⁇ zing features defined in claim 1 and by a piping system of the kind described in the introduction which has the cha ⁇ racterizing features defined in claim 2.
  • the solution to the problem has been achieved by using a few simple and reliable components which also function in the event of an electric current failure.
  • the solution according to the present invention is partly based on a discovery which is completely incompatible with the knowledge accepted up to now as to how pipe rupture during freezing occurs, and on which all the previous attempts for a satisfactory solution have been based.
  • Trials carried out by me under controlled conditions in a research laboratory have namely shown that pipe rupture during freezing does not occur at the ice plug formed but at a part of the pipe where the water has not yet frozen.
  • a growing ice plug can give rise to a pipe rupture at a place 100 m from it. This explains why temperature controlled frost prevention devices have not been able to solve the problem. It is not possible to measure the tem ⁇ perature everywhere in the water piping system.
  • the present invention is also based on a known property of water which has not been utilized so far in this connec ⁇ tion, i.e. that the volume of a given quantity of water decreases with falling temperature down to +4 C, to sub ⁇ sequently increase when the temperature continues to fall from +4 C to the freezing point.
  • This situation is illustrated in the diagram in Figure 3 and will be explained in more detail below in conjunction with the description of an embodiment example, and with reference to the Figures on the drawings, of which
  • FIG. 1 illustrates purely schematically water pipe of a piping system for carrying out the method in accordance with the invention
  • Figure 2 is a diagram illustrating how the freezing point of water is lowered for increasing pressure
  • Figure 3 is a diagram illustrating theoretically how the pressure in an entrapped quantity of water varies with the temperature
  • Figure 4 shows in section a non-return valve in combina ⁇ tion with a second safety valve
  • Figure 5 shows in section a first safety valve adjacent the tap
  • Figure 6 shows a simple safety valve which opens when a rupture tab is broken due to over-pressure.
  • the piping system illustrated in Figure 1 includes quite simply a pipe 1 taking water under pressure from a reser ⁇ voir, water tower, pump, etc., to a tap 2.
  • a non-return valve 3 is connected in the line and allows the water to flow in the normal flow direction from the water tower, but not at all in the opposite direction, should the pressure rise in the pipe portion 1A between the non - return valve 3 and tap 2.
  • a safety valve 4 is mounted close to the tap 2 and in this simple way there has been achieved an effective protection against freezing in the pipe portion 1A of the piping between the non-return valve 3 and the tap 2.
  • the invention utilizes a property of water which has been almost unnoticed in this connection, namely that a given quantity of water assumes its least volume at a tempera ⁇ ture of +4 C.
  • a kilogram of water has a volume of 1.000028 litres at +4°C and 1.000101 litres at +1°C. Since water has extremely small compressibility, a temperature drop from +4°C to +1°C gives rise to a considerable pressure increase in a tightly closed space, such as the pipe length 1A, which is free from air.
  • Figure 3 illustrates how the pressure varies in an enclosed quantity of water with varying temperature. The change in pressure in relation to temperature can be expressed by the following formula:
  • V is a constant volume
  • k 48.8 x 10 " , ⁇ L - 0 at 4°C and i - 0.6 x 10 "4 at 0°C ( ⁇ varies linearly therebetween.
  • the non-return valve 3 prevents all backflow to ensure the desired pressure rise.
  • the non-return valve 3 may for example be placed adjacent the water meter in a housing at a place where it is desi ⁇ red to prevent formation of ice in the piping. However, the non-return valve 3 may be mounted at any place provided that there is created a sufficient pressure rise in the pipe portion 1A between the non-return valve 3 and the safety valve 4, when the water is in the neighbourhood of its freezing point.
  • the non-return valve 3 may be adjusted to open for through-flow in the normal direction of flow not before the pressure on its upstream side exceeds the pressure on its downstream side with at least 1 kP .
  • Practical tests with a half-inch copper pipe closed at both ends show that the pressure in this pipe may fall from 500 kPa at 20°G to 300 kPa at 4°C, followed by an increase to 600 kPa when the temperature reachess 0 C. There will thereafter be a pressure increase up to tens of thousands kPa before the water is changed into ice.
  • the safety valve 4 is provided to open at about 100 kPa to reduce the pressure and at the same letting out water during 10 to 15 seconds before the safety valve 4 closes again. This allows the water to be flushed through the non-return valve 3, into and through the pipe portion 1A. This procedure will then be repeated automatically if the water is once again subjected to the risk of freezing.
  • copper has a high coefficient of expansion and thus reinforces the pressure increase at temperatures below 4°C by its internal volume decreasing.
  • the safety valve at 4 the tap 2 in the form of a simple bursting tab, which bursts at the high pressures occurring when the water approaches freezing point, to allow a minor jet of water to flow until the tap has been replaced. Due to the expansion of the pipe, the pressure increase for rising temperature will not be sufficient to burst the tap (in such a case quite unnecessarily).
  • the safety valve 4 close to the tap 2 should preferably have a retarded reclosure, so that it allows the water to flow for about 10-15 seconds before it closes. This allows the water to circulate and bring new, warmer water into the pipe or pipes which are to be protected. Even for very cold te pe- ratures round the piping, there is still a rather small amount of water which flows out to waste every day. And if there is no immediate risk of freezing, no water at all will run to waste.
  • the safety valve 4 functions as a sensor monitoring the entire piping system downstream of the non-return valve 3.
  • Fig. 4 shows a known non-return valve 3 in combination with a known safety valve 5 made by Valstop, Sweden, with type number H151.
  • the non-return valve comprises a spring loaded valve member 6 opening when the pressure upstream the valve member exceeds the pressure downstream the valve member with a predetermined value.
  • the safety valve 5 comprises a springloaded valve member 7 which opens at a predetermined pressure at the place where the safety valve is connected to the pipe portion 1A.
  • Fig. 5 shows a known safety valve 4 of the type Spirax SARCO 851 T, Sweden, which is slightly modified by the provision of a water channel 8 which leads water from the pipe portion 1A through a chamber 9 to a pressure chamber 10 to press a diaphragm 11 downwardly when the pressure in the pipe portion 1A exceeds a predetermined value to open the safety valve for a predetermined period of time to let water out through the outlet 12 or the outlet 13 shown in dotted lines to indicate that this outlet may replace the ordinary outlet 12 when the pipe portion 1A is extended as shown in dotted lines and ended with the tap 2 as shown in Fig. 1.
  • a knob 14 is pushed down to press down the diaphragm. This pushing action is replaced by the pressure of the water led through the channel 8 to the pressure chamber 10.
  • valve members 15 and 16 When the valve members 15 and 16 are closed, the water pressure in chamber 9 is counteracted by the pressure of the water in the counter pressure chamber 17 and the spring 18 keeps the valve member 16 closed; whereas the valve member 15 is held by the flexible rubber sleeve 19.
  • valve member 16 opens to permit water to leave the chamber 17 which in turn results in that the water in chamber 9 moves the valve body 20 and opens the valve member 15 to admit water from the pipe portion 1A, through the chamber 9 and out through the outlet 12 or 13.
  • Fig. 6 shows a safety valve 4A having a rupture tab 4b which is shown in dotted line when ruptured.
  • the invention may be employed in any water pipe system subjected to temperatures below the water freezing point.
  • sprinkler systems and water pipings in air planes may advantageously be provided with the safety device according to the invention.
  • the water installation is sometimes subjec ⁇ ted to low temperatures such as -30°C but the freezing risk in the piping is in a simple matter eliminated by means of the invention.
  • the water supply pipe 1 is then coming from a warm water container in the air plane which will feed warm water when the safety valve or valves 4 open.
  • the non-return valve 3 is mounted, preferably together with its safety valve 5 which will function merely as an emergency under extreme conditions.
  • the safety valve 4 Downstream the pipe portion 1A the safety valve 4 is mounted.
  • the length of the pipe portion 1A may be some meters or up to hundred meters.
  • the safety valve 4 is mounted close to the tap 2, but the pipe length between the pipe portion 1A and the tap 2 may have a considerable length which is not subjected to the risk of freezing; the safety valve may be mounted at the end of the pipe portion 1A or at any place between this pipe portion and the tap 2. However, in most cases, for practical reasons, the safety valve 4 is provided close to the tap 2.
  • the pressure rises in the pipe portion 1A when the temperature passes +4 C down to about zero without any formation of ice, for reasons given above.
  • the safety valve 4 opens during a predetermed period of time. The water in the pipe portion 1A starts to flow out, the pressure is lowered to the pressure permitting the non-return valve 3 to open and relatively warm water to flow through the non-return valve, the pipe portion 1A and through the open safety valve 4, until it automatically closes at the end of the predetermined time as described in connection with the safety valve 4 in Fig. 5. Accordingly, there will repeatedly be an opening of the safety valve 4 letting out relatively small amounts of water to prevent freezing in the pipe portion 1A.

Abstract

Dans le procédé décrit qui sert à empêcher le gel dans des conduites d'eau, un clapet de retenue (3) est disposé en amont de la partie (1A) de la conduite (1) à protéger et un clapet de sécurité (4) est disposé en aval de cette partie. Le clapet de sécurité s'ouvre pour permettre à l'eau de s'écouler vers l'extérieur et empêcher le gel lors d'une augmentation de pression de l'eau enfermée en aval du clapet de retenue, cette augmentation de pression se produisant lorsque la température tombe de +4°C vers le point de congélation. La présente invention se rapporte également à un système de conduite permettant de réaliser ledit procédé.
PCT/SE1988/000133 1987-03-17 1988-03-16 Procede servant a empecher le gel dans des conduites et systeme de conduite permettant de realiser ledit procede WO1988007109A1 (fr)

Priority Applications (5)

Application Number Priority Date Filing Date Title
AT88902971T ATE66032T1 (de) 1987-03-17 1988-03-16 Methode, um das vereisen von rohrleitungen zu verhindern und ein rohrleitungssystem zur realisierung des verfahrens.
DE8888902971T DE3864142D1 (de) 1987-03-17 1988-03-16 Methode, um das vereisen von rohrleitungen zu verhindern und ein rohrleitungssystem zur realisierung des verfahrens.
DK637388A DK164178C (da) 1987-03-17 1988-11-15 Fremgangsmaade til forhindring af frysning i vandroer og et roersystem til udoevelse af fremgangsmaaden
NO885115A NO163461C (no) 1987-03-17 1988-11-16 Fremgangsmaate for aa hindre frysing i roer og et roerledningssystem for gjennomfoering av fremgangsmaaten.
FI894367A FI87001C (fi) 1987-03-17 1989-09-15 Foerfarande foer att foerhindra ett roer fraon att frysa till is och ett roersystem foer foerverkligande av foerfarandet

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SE8701098A SE456830B (sv) 1987-03-17 1987-03-17 Saett foer att foerhindra frysning i roer med backventil och saekerhetsventil samt roerledningssystem foer genomfoerande av saettet
SE8701098-9 1987-03-17

Publications (1)

Publication Number Publication Date
WO1988007109A1 true WO1988007109A1 (fr) 1988-09-22

Family

ID=20367891

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/SE1988/000133 WO1988007109A1 (fr) 1987-03-17 1988-03-16 Procede servant a empecher le gel dans des conduites et systeme de conduite permettant de realiser ledit procede

Country Status (11)

Country Link
US (1) US5014731A (fr)
EP (1) EP0349575B1 (fr)
JP (1) JPH02503213A (fr)
AT (1) ATE66032T1 (fr)
CA (1) CA1303460C (fr)
DE (1) DE3864142D1 (fr)
DK (1) DK164178C (fr)
FI (1) FI87001C (fr)
NO (1) NO163461C (fr)
SE (1) SE456830B (fr)
WO (1) WO1988007109A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2309479B (en) * 1996-01-26 2000-07-26 George Evdemon Water supply system for buildings

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5842839A (en) * 1994-03-11 1998-12-01 Walsh; Roger C. Liquid supply system
US5730168A (en) * 1996-06-14 1998-03-24 The Board Of Trustees Of The University Of Illinois Pipe burst protection pressure relief apparatus for plumbing fixtures
US6491109B2 (en) * 2001-05-11 2002-12-10 Joel P. Christenson Kinetic antifreeze device
US20040069346A1 (en) * 2002-10-04 2004-04-15 Robert Adrian Exterior sprinkler system shutoff and drainage system
US10260823B2 (en) * 2012-11-19 2019-04-16 Robert Cooney Freeze protection system with drainage control for heat transfer coils in HVAC systems
WO2015183258A1 (fr) 2014-05-28 2015-12-03 Hewlett-Packard Development Company, L.P. Gestion d'une condition de fluide dans un tuyau

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1159225A (en) * 1915-02-10 1915-11-02 John W Howell Freezing-plug.
US4117856A (en) * 1976-09-27 1978-10-03 Mark Controls Corporation Frostproof backflow preventer
US4483361A (en) * 1978-12-20 1984-11-20 Jungbert Sr Edward J Anti-syphon frost-proof hydrant

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3319657A (en) * 1964-10-16 1967-05-16 Louis A Nyiri Coil freeze protection device
US3926051A (en) * 1975-01-02 1975-12-16 Oded Katzman Frost protection plug for a water meter
EP0061908B1 (fr) * 1981-03-27 1986-08-20 David Rosser Hudson Contrôle et mesure de fluide
US4776362A (en) * 1984-11-07 1988-10-11 Domingue Sr Chris J Relief valve for fluid line

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1159225A (en) * 1915-02-10 1915-11-02 John W Howell Freezing-plug.
US4117856A (en) * 1976-09-27 1978-10-03 Mark Controls Corporation Frostproof backflow preventer
US4483361A (en) * 1978-12-20 1984-11-20 Jungbert Sr Edward J Anti-syphon frost-proof hydrant

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2309479B (en) * 1996-01-26 2000-07-26 George Evdemon Water supply system for buildings

Also Published As

Publication number Publication date
NO163461B (no) 1990-02-19
FI87001C (fi) 1992-11-10
NO885115D0 (no) 1988-11-16
DK164178C (da) 1992-10-12
EP0349575A1 (fr) 1990-01-10
JPH02503213A (ja) 1990-10-04
US5014731A (en) 1991-05-14
NO885115L (no) 1989-01-16
SE456830B (sv) 1988-11-07
DK637388D0 (da) 1988-11-15
FI894367A0 (fi) 1989-09-15
ATE66032T1 (de) 1991-08-15
DK164178B (da) 1992-05-18
DK637388A (da) 1989-01-12
DE3864142D1 (de) 1991-09-12
FI87001B (fi) 1992-07-31
EP0349575B1 (fr) 1991-08-07
NO163461C (no) 1990-05-30
SE8701098D0 (sv) 1987-03-17
CA1303460C (fr) 1992-06-16
SE8701098L (sv) 1988-09-18

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